The present invention generally relates to circuit boards. The invention particularly relates to methods of identifying circuit boards.
Printed circuit boards (PCBs) are often manufactured and assembled while part of an array of PCBs within a panel to enable multiple PCBs to be manufactured and assembled at the same time using automated processes. A panel may be in the form of a multilayer blank (board). The blank may comprise any suitable number of layers formed of various materials. For example, the blank may include a laminate base having a thin copper layer on one or more surfaces thereof. An image may be applied to surfaces of the blank representative of (as nonlimiting examples) traces and pads of the desired circuit board. Imaging is often performed with high intensity ultraviolet light and chemical processes known in the art. The resulting image effectively exposes portions of a copper layer of the blank while covering other portions of the copper layer. Etching processes are performed to remove the exposed portions and expose the laminate base thereunder. The remaining portions of the copper layer, which were covered during the etching process, generally define features such as traces and pads. An oxide coating may be applied to the remaining portions of the copper layer to improve adhesion to their surfaces. At this point, additional layers, including layers of copper foil, may be added to the blank through one or more lamination processes.
After various processes to prepare the blank for circuit components, the blank may then be marked to include, for example, component placement, part numbers or names, date codes, logos or other specified information relating to each board to be fabricated from the blank, after which various other processes may be performed on the blank to result in a multilayer blank suitable for producing the intended panel and its circuit boards.
The individual circuit boards within a panel often carry markings that may include the identity of the manufacturer, part numbers, board dimensions, model numbers, versions, date codes, and/or other identifying information capable of identifying the boards after they have been placed installed in a computing system. Conventionally, these identifying markings may be printed on components mounted to the circuit board and/or printed on portions of the circuit board surfaces that are not occupied with components, for example, by inking processes performed on outer layers of copper that were applied to the panel during its manufacture. These processes often add additional steps, time, and expense to the manufacturing process of a circuit board. In addition, as the sizes of circuit boards are reduced and denser component placement is sought, there is less space on circuit boards where identifying markings may be located and remain visible in the final circuit boards.
In view of the above, there is a long felt need for marking circuit boards with identifiers and/or other identifying information relating to the boards while reducing the additional steps and time, and associated expenses.